Friction shock-absorbing mechanism



May 25 1926.

J. F. O CONNOR FRICTION SHOCK ABSORBING MECHANISM 2 Sheets-Sheet 1 Filed July 25. 1925 M m ....hw

May 25 1926. "1,586,322

J. F. OCONNOR FRICTION SHOCK BSORBING VNIEGHNISM Filed July 23, 1925 patented May 25, 1926.

UNITED STATES PATENT'OSFFCBE.'

JOHN F. OCONNOR, GF (EI-I IfJAfalOJ ILLXNOISAS'SIGNORyBY MESNE ASSGNMENTS, TO

W. H. MINER, INC., A CORPORATION OF DELAWARE. i

FICTION SHOCK-ABSORBING MECHANISM.

Application led `lilly 23, 19E/33.k Serial` No 653,114.

This invention relates to improvements in friction shock absorbing mechanisms.

One object of the invention is to providel a friction shock absorbing mechanism, more particularly adapted for railway draft riggings, whereinis obtained high capacity due to the large frictional areas, and wherein a differential wedge action is made Luse of to assure quick and certain release of aphirality of friction plates.

Another object ofthe invention is to provide a friction shock absorbing mechanism of the type referred to wherein graduated action in both compression and release is ob'- tained by producing` a preliminary action of the followers and wedges prior to engage.- meiit and relative movement of the friction plates. y

, Other objects and advantages of the invention will inoreclearly appear from the description and claims hereinafter following. y n

In the drawings forming a part of this specification, li`ignre 1 is a horizontal, longitudinal, sectional View of a portion of a railway draft rigging showing my` improveineiits` in connection therewith. Figure 2 is a vertical, transverse sectional view corresponding substantially to the line 2-2 of Figure 1. Figures 3 and 4 are detailed side elevational views respectively of a stationary and a relatively movable friction plate. AndFigure 5 is a horizontal, longitudinal sectional view of the shock absorbing mechanism proper, the front and rear followers being omitted, illustrating a different embodiment ofthe invention.

In said drawings, referring first to ures 1 to l inclusive, 10-,1O denote channel draft sills of a car underframe, to the inner faces of which are secured front stop lugs 11 and rear stopy lugs 12. A portion of the drawbar is indicated at 13, the same being operatively associated with a hooded cast yoke 14 within which .is kdisposed the shock absorbing mechanism proper, av front follower 15 and a rear follower 16. The yoke and the part-s therein are supported in opf erative position by a detachable saddle plate 17. j o

The improvedshcck absorbing mechanism proper, as shown in Figures 1 to l inclusive, comprises broadly, and springl cage casting A; a central wedge a pair of wedge friction shoes C-Gg two a combined friction shelly vseries of movable friction plates D-D; two

series of relatively stationary friction plates E-F; a spring resistance element Fia spring follower plate G; and a retainer bolt H. i i

rfhe' eastingA is provided at its front or outer end with a friction shell proper defined by top and bottom walls 18-18 and side walls 19-19, the latter being provided on their inner sides with flat surfaces 20-20 converging' slight-ly inwardly ofthe shell. Rearwardly ofthe shellproper, the casting Avis reduced in size to provide a rspring cage 21 casing to accommodate and center the spring resistance F. At its rear end the casting A is formed` with an integral vertical wall 22 extended laterally to engage with thek rearfollower 16. Rearwardly of the converging faces 20, the side walls 19 are cut away as indicated at 23. Transverse shoulders 2l adapted to form abutments for the rear ends of the stationary friction plates E are presented at thel point o-f reduction of the shell proper. Adjacent the rear end of the `shell proper and spaced outwardlyfrom theshoiilders 24 the upper and lower walls 1S of the shell are provided with upwardly and downwardly projecting ribs `2`5ve1-1tending inwardly from the side walls 19 ashort distance; the inner ends of the same being spaced apart a sufficient distance to accommodate the spring resistance therebetween. At the front endof the shell proper, the side walls thereof are provided with inwardly projecting short flanges 26, thereby presenting vertically exten'dingstop shoulders 27.

The central wedge B is in the form of. a hollow block having `laterally extending flanges 28. The wedge bloclr B is provided with a fiat front face 29 adapted to abut the. front follower 15 and a pair of rearwardly converging flat wedge faces 30. i

The friction wedge shoes C are of like construction and are arranged on opposite sides of the central wedge B. Each of the friction -slioes C is in the form of an elonf gated bloclr having lateral extensions 31 projecting inwardly toward the aXis of the mechanism. Each of the extensions 31 is soy provided with a front wedge face 32 ,corref spondingly incline-dr to and co-operating with the adjacent wedge face 30 of the wedge B and fiat rear face adapted to co act with a spring follower G. At the outery side each of the friction wedge shoes is provided with a relatively long flat friction face 33 adapted to co-act with the adjacent innermost friction plate D. At their upper and lower sides, the wedge shoes C are formed with laterally extending vertically spaced lugs 3st for a purpose hereinafter described.

The friction plates D and E are disposed within the friction shell and comprise two oppositely arranged groups. As herein shown, the groups of plates each comprise three platesD and four plates E, the plates D and E being alternated, with two plates E of each group arranged respectively outer and innermost in cont-act with the inner surface 20 of the adjacent side wall 19 and the eongated friction surface 33 of the corresponding shoe C. Upon reference to Figure l, it will be seen that the plates D and E composing each group are thus arranged parallel to the adjacent friction surface 20, so that the two groups of opposed plates diverge inwardly with reference to each other.

T he plates D are all of like construction, and as best shown in Figure 3, each of the same is formed with relatively long upper and lower vertical y alined slots between the ends thereof, the slots 35 being spaced a greater distance from the front end of the plate than from the rear end thereof. The slots 35 of each plate D are adapted to coact with the upper and lower lugs 34 of one of the wedge shoes C, the slots being of an appreciably greater length than the width of the lugs, so that each set of four plates D and the adjacent shoe C may have limited relative movement.

The plates E are all of like construction, and as best shown in Figure i each of the same is provided with upper and lower vertically alined short slots 36 near the rear end thereof. The slots 36 of the plates E correspond in length to the width of the ribs 25 which they are adapted to receive. The plates E are thus anchored to the casting A, the slots 36 and ribs 25 being so spaced with reference to the transverse walls 24 that the rear ends of the plates abut the walls. The p`ates E are of such a length that the front ends thereof are disposed inwardly of the outer end of the shell as clearly shown in Figure l. The plates E are thus held against outward movement by ribs 25, and against inward movement by the combined action of the ribs and walls 24. It will be evident that the walls 24 provide a solid abutment for the plates E which assume a large proportion of the forces applied during compressive action of the mechanism.

' The spring resistance element F comprises a relativ-ely heavy outer coil and a relative lighter inner coil. The outer coil has its opposite ends abutting respectively, the rear wall 22 of the casting A and the spring follower plate G, the rear end of the spring being centered by an inwardly projecting hollow boss 3T on the rear wall 22 of the cage. rihe innercoil has its opposite ends abutting respectively the spring follower and the end of the boss 3T.

rlhe shock absorbing mechanism is held in assembled relation and under initial compression by the retainer bolt H passing through the inner coil of the spring resistance and alined openings in the wedge block B, spring follower plate G and boss 3T, having its opposite ends anchored in the wedge B and the boss 3l', respectively,

lVhen the parts are in normal position, as clearly shown in Figure l, the friction plates D protrude from the shell and have their front ends slightly spaced inwardly from the flanges 28 of the wedge B, the front edges of the lugs 34: of the shoes being in engagement with the outer end walls of the slots 35 of the plates D, and the shoes being held in their outermost position by the action of the spring resistance F.

The operation of the improved shock absorbing mechanism shown in Figures l to l inclusive, is as follows, assuming an inward or buliing movement of the drawbar. Upon inward movement of the draw bar, the follower 15 will be forced inwardly, thereby moving the wedge B simultaneously and uniformly therewith. As the flanges 28 of the wedge are normally spaced from the plates D, there will be no action of the plates D during the initial movement of the wedge, but the entire wedging system, inclu-ding the wedge B, shoe C, together with the spring follower plate G will be moved longitudinally inwardly against the resistance of the spring independently of any movement of the plates D. It will be evident, that, as the innermost plate of each group on which the corresponding wedge shoe slides is always held against movement longitudinally of the shell, the movement of the shoes will have no effect on the movable plates D.

During this first part of the compression stroke, it will be evident that the lugs 34 on the wedge shoes C will be moved from engagement with the front walls of the slots 35 of the plates D, this movement of the lugs being permitted by the relatively great length of the slots 35.

Furthermore, a wedging or spreading action will be set up between the wedge and the shoes, and a differential wedge action will also be had due to the converging relation ofthe innermost lined plates E on which the shoes C slide, thereby further compressing the spring resistance.

After the initial movement of the follower l5 and the wedge system including the wedge B, the flanges 28 of the wedge engage the yplates D and thereafter the lattermove in unison with the wedge B, thus 4generating the desired frictional capacity ysupplemental to the spring capacity, the stationary plates being effectively held against inward movement by the abutn'ient walls 24. Movement of the front follower will finally be limited by engagement with the front end of the casting A, the pressure being 'directly transmitted through the casting tothe rear follower, the casting acting as a pressure transmitting column when -the mechanism has been fully compressed. n

Upon removal of the actuating force, the springs are free to expand and in so doing force the Afollower Gr, shoes C and the wedge B outwardly relatively to all of the friction plates. This action is instantaneous and eX- tremely sensitive for the reason that there is no movement of any of the friction plates during the initial part of the release action and that the innermost plates with which the shoes co-act are arranged in outwardly diverging relation. ing system and forcing the same outwardly a limited distance, the pressure on the friction plates will have been reduced substantially to a minimum and upon the lugs 34 coming into engagement with the outer walls of the slots 35, of the plates D, the latter may be easily projected outwardly to the normal position.

It will be evident that there will be no movement of the `outer plates E on the converging surface of the shell during either compression or release, and that these plates therefore serve as liners in addition to acting as friction plates.

As the different friction and wedge surfaces become worn, compensation therefor is had by the expansive action of the spring, which is under initial compression, as hereinbefore described.

Referring next to the construction illustrated in Figure 5, the arrangement is generally the same as that hereinbefore described except that a casing A is of box-like form, that the stationary plates E are `held against longitudinal inward movement solely by a transverse rib 125 corresponding to the rib 25, that the groups of plates each compose three movable and three relatively stal tionary plates D and that the movable plates are moved inwardly longitudinally of the shell by flanges on thewedge shoes C instead of being moved directly by the wedge B. The relative arrangement of the plates of each group is also somewhat different due to the same comprising an equal number of fixed and movable plates, a movable plate D of each vgroin; being arranged outermost and having sliding engagement with the adjacent inner surface 120 of the correspondingside wall of the shell. The inner surfaces 120 of the side walls -onverge rearwardly of the After releaseof the wedg- Y c shell and the opposite groups `of plates also` converge rearwardly correspondingly. n

The centralwedge block B is provided with a yflat front face 129 adapted to engage the frontfollower and rearwardly converging wedge faces 130, each adapted to co-act with any outer wedge face 132 on the corresponding shoe C. Each of the shoes C" is provided with alateral flange 140at the forvward'end thereof normally slightly spa'ced from the front ends ofthe plates D and adapted to co-act therewith in7 a manner similar to the flanges 28 ofthe wedge B to move the plates D." inwardly lengthwise of the shell after the wedging action has been set up. Each of the shoesC is also provided with a laterally projecting lug 141 at the rear end thereof adapted to work in horizontally extending relatively .long slots in the stationary plates E of the adjacent group and engage with the rear ends of the movable plates D of sai'dgroup to restore the same to normal position.

It will be evident that the shoes C willy be moved rearwardly by the wedge B during the compression of the mechanism and that while the flanges 140 of the shoes approach the front ends of the plates D during initial action of the mechanism, the lugs 141 will be moved rearwardly and out of engagement with the plates E, functioning similarly to the lugs 34. The construction, arrangement and operation of the spring resistance F, spring follower G and retainer bolt I-I is identical in all respects with the corresponding parts shown in Figure 1.

I have herein shown and described what I now consider the preferred manner of carrying out the invention, but the same is merely c illustrative .and I contemplate all j changes and modifications that come within the scope of the'claims appended hereto. I claim: 1. In a friction shock absorbing mechanism, the combination with ashell; of an outer follower movable relatively toward and from the shell; a lateral wedge pressure creating means co-acting with said follower, said means including friction shoes; a plurality of intercalated friction elements within the shell, said elements being divided into two inwardlyv converging groups on opposite sides of said wedge pressure creating means, alternate plates of each group being anchored to the shell and the remaining plates being movable relatively thereto during a compression stroke; a means within said shell for yieldingly resisting inward movement of said shoes independently of said movable friction elements; and means on said shoes engagingsaid movable elements to restore the same to normall position.

2. Ina friction shock absorbing mechanism, the combination with a shell provided atk with interior rearwardly converging surfaces; of an outer 'follower movable relatively toward and from the shell; a Wedge movable with said follower, friction shoes co-acting with said Wedge, each of said shoes having' a friction surface arranged parallel to the corresponding linterior eurface of the shell; means for yieldinglv resisting rearward movement of said shoes; and a plurality of longitudinally arranged intercalated friction elements within said shell, said elements being` divided into groups on opposite sides of said shoes and adapted to cO-act with the friction surfaces thereof, the elements composing each group being arranged in parallel relation to each other and the adjacent inner surface of said shell, alternate elements of each group being anchored to said shell and the remaining elements being; also movable relatively to said anchored elements during; a compression stroke, said movable elements and shoes having` inter-engaging` stop shoulders for effecting restoration of the last named elements to normal position and permitting limited relative movement between the same and the shoes.

In Witness that I claim the foregoing` I have hereunto subscribed my name this 19th day of July7 1923.

JOHN F. OCONNOR. 

